If Vince is truly serious about pushing Smackdown more towards being the "A" show, the choice would be easy as to how to do it. Now I'm not really sure, even though I read the exclusive article to which the OP refers, that Vince is actually serious about trying to make Smackdown the "A" show and RAW the "B" show, and even if he is serious, I'm not sure how realistic it would be to do it. RAW has been around longer. It is live while Smackdown is pre-recorded. I know SD just changed stations, but I would suggest that SyFy is not as significant a station as USA. So I feel no matter what, RAW will always be the "A" show and SD will always be secondary to it.
If Vince wanted to really try to do it, though, the easy way to do it is to move John Cena. This could be done in one of two ways. One possibility would be to have Cena actually go full heel, ie, to start off as a reluctant unwilling member of the Nexus, but have him lured to the "dark side" by the power, by the numbers, by always having someone by his side to watch his back,and have him do the full heel turn and move the whole heel faction of the Nexus, with Cena central to it, to Smackdown. This would definitely boost the ratings that SD achieves and would be a breath of fresh air into Cena's character as well.
The other possibility would be to have Cena finally reach his breaking point with Wade Barrett and the rest of Nexus. Have him smack Barrett in the mouth and refuse to be his whipping boy any more, at which point, the mystery GM fires him: from RAW. Not fired from all of WWE, just fired from RAW only. At which point Teddy Long snaps up the unemployed John Cena and brings him to SD. Either way, Cena moves to Smackdown and gives this brand a shot of life. Would be interesting to see, actually, what if any difference this would make to the ratings of either brand.